Systems and methods for forming an isolated transformer

Abstract

A transformer to isolate a primary winding from a signal winding include a primary substrate (which may comprise a printed circuit board (PCB)) and a secondary substrate. The primary and secondary substrates may each have three openings to allow first and second E-E core halves to be joined therebetween. A first insulator may be disposed between the primary and secondary substrates to isolate the primary substrate from the secondary substrate. A second insulator may secure the primary and secondary substrates in place and insulate the secondary substrate from the core. The primary and secondary substrates may each include a Faraday shield its outer layers. A shield slit to prevent shorting between the legs of the E-E core may be formed by cutting a channel in the shield between the opening of the primary and secondary substrates. A retaining clip may be used to clamp together the primary substrate, first and second core E-E core halves, secondary substrate and second insulator. A primary winding and sense winding may be disposed within the primary substrate and a signal winding may be disposed within the secondary substrate. The primary, sense, and signal windings may be positioned so that the magnetic flux produced by the primary winding passes through the signal and sense windings in substantially equal proportions. The primary and signal winding may enter the E-E core from opposite directions to choke any common mode current therebetween.